If it were me, I'd have at least 1 meal a day with solid food. I don't think it would hurt to do that & I bet you'd feel better too with a little bit of real food in you. But like I said, that's just me. Something along the lines of grilled steak, grilled chicken, grilled halibut, blackened swordfish, baked potatos, rice, grilled veggies, etc. Those would be good choices. Then the rest of the time do as you planned.......sipping on 3-4 protien drinks throughout the day. I like doing a bunch of push ups & situps when I'm on vacation if I don't have access to a work out facility. You could mix some of that stuff in with your running if you wanted to.
Also, you didn't mention this but....are you going to be drinking alcohol while you're there? That might be another reason to include a little solid food in your diet while you're there. jmo....